1. Field of the Invention
The present invention relates to an information reproducing method and apparatus for reproducing information from a recording medium and an information recording medium used in the apparatus.
2. Related Background Art
Various protect methods of preventing illegitimate coping operations are known in distributing information recording media such as floppy disks upon recording software or information thereon. Many of these protect methods are based on the advantages that a floppy disk drive can form a software format and generate sectors and sector addresses accompanying the sectors, and the physical addresses of a floppy disk can be directly accessed from application software. That is, many conventional protect methods are designed to inhibit access to the sectors of a floppy disk by placing the files of the floppy disk outside the control of an OS (operating system).
Recently, optical disk units and magnetooptical disk units using optical disks and magnetooptical disks as recording media have been developed. These units are expected to be widely used as external memory units for computers. For this reason, it can be said that the importance of the above protect methods of preventing illegitimate copying operations is on the increase in such optical disk and magnetooptical disk units as well.
Since sectors and sector addresses are recorded on an optical or magnetooptical disk by using embossed pits, sectors and addresses accompanying the sectors cannot be generated by an optical or magnetooptical disk unit. In addition, an optical or magnetooptical disk unit uses a SCSI interface. Since this SCSI interface supports logical addresses, an application program cannot directly access physical addresses. For this reason, a floppy disk unit is basically different from an optical or magnetooptical disk unit. Therefore, it is difficult to directly apply a protect method for a floppy disk unit to an optical or magnetooptical disk unit.